Identifying forces on a tooth

ABSTRACT

The present disclosure includes computing device related, systems, and methods for identifying force placed on a tooth are described herein. One method includes receiving initial orthodontic data (IOD) including teeth data; creating a virtual set of teeth from the IOD; receiving dental appliance information including at least one of dental appliance material properties and characteristics; virtually placing a dental appliance, formed from the dental appliance information, onto the virtual set of teeth; and determining one or more forces applied to the teeth based on information from the IOD and dental appliance information.

CLAIM OF PRIORITY

The present application is a continuation of U.S. patent applicationSer. No. 15/195,588, filed Jun. 28, 2016, titled “IDENTIFYING FORCES ONA TOOTH,” now U.S. Pat. No. 11,426,259, which is a continuation of U.S.patent application Ser. No. 13/365,167, filed on Feb. 2, 2012, titled“IDENTIFYING FORCES ON A TOOTH,” now U.S. Pat. No. 9,375,300, each ofwhich are incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to systems and methods for virtuallyidentifying forces placed on teeth.

BACKGROUND

Many dental treatments involve repositioning misaligned teeth andchanging bite configurations for improved cosmetic appearance and dentalfunction. Orthodontic repositioning can be accomplished, for example, byapplying controlled forces to one or more teeth over a period of time.

An example of orthodontic repositioning that can occur through a dentalprocess uses one or more positioning dental appliances, such asaligners, for realigning teeth. Placement of an appliance over the teethcan provide controlled forces in specific locations to gradually movethe teeth into a new configuration. Repetition of this process withsuccessive appliances in progressive configurations can move the teeththrough a series of intermediate arrangements to a final desiredarrangement.

Typically, in order to design each aligner, the progression of the teethfrom an initial position to a final position is determined, via acomputing device. This progression is then segmented into a plurality ofsegments and an aligner is formed that is based upon each of thepositions of the teeth at those segments.

Currently, a treatment plan is designed by beginning with a currentteeth configuration, proposing an end configuration, generating, via acomputing device, a path for the teeth from the current configuration tothe end configuration, and segmenting that path into multiple segmentsand forming the appliances based on the data from each of thesesegments.

Each appliance may then be sequentially placed on a patient's teeth withthe theory that the dental appliance will act on the teeth to move eachtooth in a particular direction toward its position of the nextprogressive segment. However, in some instances, the appliance does notmove the teeth to the position of the next progressive segment for anumber of reasons, as discussed below. Accordingly, in these instances,the treatment plan then has to be revised and new aligners created toremedy the different than anticipated positioning of one or more of theteeth.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates an initial virtual dental model according to one ormore embodiments of the present disclosure.

FIG. 1B illustrates a target virtual dental model corresponding to theinitial virtual dental model illustrated in FIG. 1A according to thepresent disclosure.

FIG. 2 illustrates an example of an initial virtual dental model, adental appliance, and an example of a user interface according to one ormore embodiments of the present disclosure.

FIG. 3 illustrates an example of virtual three-dimensional dentalappliances with identified forces and an example of a user interfaceaccording to one or more embodiments of the present disclosure.

FIG. 4 illustrates an example virtual three-dimensional tooth model andan example of a user interface for identifying force placed on a toothaccording to one or more embodiments of the present disclosure.

FIG. 5 illustrates an example virtual three-dimensional tooth model andan example of a user interface for identifying force placed on a toothaccording to one or more embodiments of the present disclosure.

FIG. 6 illustrates a system for virtually identifying force placed on atooth according to one or more embodiments of the present disclosure.

FIG. 7 is a flow chart illustrating a method for identifying forceplaced on a tooth according to one or more embodiments of the presentdisclosure.

DETAILED DESCRIPTION

Embodiments of the present disclosure include computing device related,system, and method embodiments for virtually testing force placed on atooth are described herein. For example, one or more embodiments includea method of virtually identifying force placed on a tooth. Some suchmethods can include, for example, receiving initial orthodontic data(IOD) including teeth data, creating a virtual set of teeth from theIOD, receiving dental appliance information including at least one ofdental appliance material properties and characteristics, virtuallyplacing a dental appliance, formed from the dental applianceinformation, onto the virtual set of teeth, and determining one or moreforces applied to the teeth based on information from the IOD and dentalappliance information.

One or more embodiments can virtually place a dental appliance withcavity geometry of the first stage of the treatment plan over the IODand identifying actual forces applied to the teeth contained in the IODby the dental appliance. One or more embodiments can include determiningdesired forces to be applied by the dental appliance to move the teethto the first stage teeth positions, and designing optimized dentalappliance cavity geometry and/or position to reach the desired forces tomove teeth to the next stage teeth positions based on the dentalappliance material properties, characteristics, and shape of teeth.

Embodiments of the present disclosure can be utilized in the design ofdental appliance products for use in the mouth of a patient, such asanchors and other attachments and potentially to aligner surfaces (e.g.,dimples, ridges, thickness, shape, orientation, etc.), materialproperties, and their interaction with the teeth. Embodiments can allowa user to identify the forces present on a set of teeth on one jaw ofthe mouth or on both jaws (e.g., as tooth and/or appliance surfaces onopposing jaws interact with each other).

Various embodiments can be beneficial in determining how much force toapply to each tooth and the teeth as a whole and components of forcefrom what one or more directions and/or types (e.g., linear, torsional,etc). This information can be, for example, used to determine the shapeand/or positioning of the dental appliance or other item for themovement of teeth to get closest to the force and/or direction desiredfor moving the teeth.

For example, at present, a dental appliance (e.g., an attachment oraligner) having an already designed shape may be placed on a patient'stooth or teeth with the theory that the dental appliance will act on thetooth to move it in a particular direction. However, this theory istypically part of a treatment plan selected, based upon experience withthe type of dental appliance, by a treatment professional and the actualresult, based on the actual forces at work including those from otherteeth and other dental appliances and/or other items being utilized forthe movement of the teeth, may result in a different orientation thanexpected. This can, therefore, result in more, less, or differentmovement to achieve the desired result.

Accordingly, the forces acting on the teeth and their movements have notpreviously been considered in the analysis of the applianceconfigurations. Through use of the embodiments of the presentdisclosure, it may be possible to shape the appliances based on forcewhich may, for example, reduce the number of treatments or movementsand/or reduce the amount of force used, which may result in lesstreatment time and/or reduced patient discomfort, among other benefits.

Embodiments of the present disclosure can allow the user to virtuallytest the shape and/or placement of an attachment and/or other appliancestructure with the perspective of its effect on multiple teeth (e.g.,the whole set of teeth on the jaw). Embodiments can also makeadjustments to the shape and/or placement and/or retry the movementuntil the best or most satisfactory result is achieved.

In some embodiments, initial orthodontic data (IOD), for example, froman actual patient's mouth, typodont data, and/or scanned appliance datacan be obtained and the forces, desired during a portion of a treatmentplan to move a tooth from one position to another, can be determined.The use of actual case data (e.g., from a particular current patient'smouth or a prior patient's mouth) can be used, for example, where adental appliance may be desired to perform a particular movement withrespect to a particular tooth positioning due to a particularmalocclusion.

Treatment plan case data can be analyzed to determine the movement of aparticular tooth from one position to a subsequent position based uponthe movements of the other teeth and/or other structures in thepatient's mouth. This information can then be utilized, for example, inan embodiment's analysis of forces with respect to one or more proposedattachments and/or other aligner related movement analysis.

Embodiments of the present disclosure can provide a user interface wherea virtual model of the teeth is presented in three dimensions. Once theforces and moments of the forces are determined (e.g., through use ofIOD and/or dental appliance data), they can be presented on the userinterface (e.g., they can be presented as vector arrows showingdirection and/or magnitude of desired force) among other informationabout the force that may be helpful to the user.

These forces can, for example, include forces from any dental applianceson the tooth, forces from neighboring teeth, gingival forces appliedand/or modified for effects from other teeth on the set and their forcesand/or movements, forces from bone structures and/or other forces thatmay affect the tooth. Some embodiments can utilize appliance wallthickness and/or feature data (e.g., data about features such asdimples, reinforcement structures). This information can, for example,be measured based on an actual appliance, measurements taken from avirtual model, and/or estimated based upon thickness sampling ofmeasurements taken from previous appliances.

In some instances, it can be this combination of forces (some forces canbe additive, neutral, or subtractive to each other) that may bedifficult to ascertain without use of embodiments of the presentdisclosure. Accordingly, embodiments of the present disclosure can moreaccurately estimate the forces that are to be used. In some instances,such analysis could move a tooth more directly to a targeted locationand avoid additional movements that might be need if the analysis wasnot done. In some embodiments, a greater or lesser force can bedetermined to be used to begin tooth movement and therefore, thetreatment can be more effective.

In some embodiments, the force can be quantified with respect to asingle point, such as the center of mass or the center of rotation,associated with a tooth or can be associated with one or more contactsurfaces of a tooth (e.g., contact with other teeth or contact with theappliance).

Embodiments of the present disclosure can include many tools for thecreation and alteration of the dental appliances or other items relatedto the movement of the tooth. These items can include one or morelibraries of tooth shapes and treatment plan data (e.g., orthodonticdata such as typodonts, actual patient tooth data, and/or treatment plandata), dental appliance shapes, data regarding mounting materials thatcould be used, and/or data regarding other characteristics of a dentalappliance or tooth or mouth structure that may be beneficial indetermining a force.

Some embodiments also include editing tools to change the shape of thedental appliances or other items related to the movement of the tooth.For example, suitable tools could include those typically provided withrespect to drafting and/or computer aided design software applications.

In some embodiments, the desired forces and the actual forces can beillustrated on the virtual model so that the user can see thedifferences between the actual and desired forces (e.g., force and/ormagnitude vectors for both the desired and actual forces). This can behelpful, for example, by allowing the user to see the differences andadjust the shape or position of the dental appliance or other itemrelated to the movement of the tooth.

The actual force can then be recalculated and then illustrated to showthe revised force of the revised shape and/or position, in someembodiments. The resulting effect can be shown on the other teeth of theset in some embodiments, which may help the user identify any incidentalissues with a proposed treatment plan or dental appliance positionand/or shape.

In some embodiments, multiple calculated positions and/or shapes can beillustrated (e.g., the forces generated from a first position and asecond position can be illustrated together and, in some instances, withthe desired forces). This can be beneficial, for example, to identifyhow the change from a first to a second position affected the forces. Itcan also be beneficial to identify if the change from a first to asecond position is adjusting the forces created closer to those of thedesired forces, among other benefits.

Embodiments can, for example, utilize Discrete Differential Geometry forits calculations versus other systems using Finite Element Analysis. Thecan be beneficial, for example because, such embodiments can docalculations much quicker and/or with less computing time and/orresources, in many instances.

Various embodiments, can be used to determine what the resultingconfiguration of teeth would be based upon the appliance proposed in thetreatment plan. This can be beneficial, for example, to determinewhether the appliance proposed would move the tooth as desired, ifanother type of appliance should be used, or if the appliance should beredesigned to provide the desired movement of the tooth.

Some embodiments can identify if the appliance will stretch and wheresuch stretching will occur. This can be beneficial, for example, toidentify points in which the appliance should be reinforced to reduce oreliminate the stretching.

One proposed method includes: receive initial orthodontic data (IOD) ofteeth of a patient, identify a virtual target dental model of the teethbased on the IOD representing a treatment plan, identify one or morevirtually created dental appliances utilized in the treatment plan,compute one or more desired force parameters of a dental appliance toachieve a final position of a particular segment of the treatment plan,and estimate actual forces generated by the virtually created dentalappliance as applied to one or more teeth and verify the virtuallycreated dental appliance is applying a desired force parameter to theone or more teeth.

Another method includes the following elements: receiving initialorthodontic data (IOD) of teeth, receiving desired tooth positions of atreatment plan for the teeth contained in the IOD, computing a desiredforce and a desired torque to be applied to the teeth to reach thedesired tooth positions, and designing an optimized dental applianceshape and position to move teeth to the desired tooth positions.

Embodiments of the present disclosure can also be beneficial for reasonsincluding, utilizing real world force information, tooth data, and/orother structural data to calculate the position for placement and/orpotential shape of an dental appliance or other appliance feature and/orgeneral shaping of an appliance without actually having to test all ofthese iterations in an actual patient or group of patients.

In the following section of the detailed description of the presentdisclosure, reference is made to the accompanying drawings that form apart hereof, and in which is shown by way of illustration how a numberof embodiments of the disclosure may be practiced. These embodiments aredescribed in sufficient detail to enable those of ordinary skill in theart to practice a number of embodiments of this disclosure, and it is tobe understood that other embodiments may be utilized and that process,electrical, or mechanical changes may be made without departing from thescope of the present disclosure.

The figures herein follow a numbering convention in which the firstdigit or digits correspond to the drawing figure number and theremaining digits identify an element or component in the drawing.Similar elements or components between different figures may beidentified by the use of similar digits. For example, 208 may referenceelement “8” in FIG. 2 , and a similar element may be referenced as 408in FIG. 4 .

As will be appreciated, elements shown in the various embodiments hereincan be added, exchanged, and/or eliminated so as to provide a number ofadditional embodiments of the present disclosure. In addition, as willbe appreciated, the proportion and the relative scale of the elementsprovided in the figures are intended to illustrate the embodiments ofthe present disclosure, and should not be taken in a limiting sense. Asused herein, “a number of” something can refer to one or more suchthings.

Although the overarching term “orthodontics” is used herein, the presentdisclosure may relate to treatments of an orthognathic nature. Forexample, in cases including treatment of a patient's underlying skeletalstructure, teeth may be rearranged by surgically repositioningunderlying bones that hold the teeth in order to achieve a desired finalbite arrangement. In both orthodontic and orthognathic treatmentapproaches, alignment of the teeth may be evaluated pre-, mid-, and/orpost-treatment.

Treatment professionals typically select a treatment plan for apatient's teeth based upon experience with certain types of physicalfeatures and/or dental appliances to be used. An assumption is oftenmade that the dental appliance will move the teeth or a certain tooth ina particular direction based on the shape of the dental appliance.

However, an actual result based on the actual forces at work may resultin a different orientation than expected, which may be an undesiredresult. With the use of computing device executable instructions, atreatment professional can establish a custom treatment target specificto each tooth or a set of teeth for each individual patient. With thistreatment target in mind, a force applied to a tooth by a dentalappliance can be virtually identified and tested.

Virtual dental models from a scan of a patient's dentition can beprovided with computer-aided design and/or manufacturing systems,including tooth-treatment systems. An initial orthodontic data (IOD)representing an initial tooth arrangement may be obtained in a varietyof ways.

For example, the patient's teeth may be imaged to obtain digital datausing direct and/or indirect structured light, X-rays, three-dimensionalX-rays, lasers, destructive scanning, computer-aided tomographic imagesor data, magnetic resonance images, intra-oral scanning technology,photographic reconstruction, and/or other imaging techniques. The IODcan include an entire mouth tooth arrangement, some, but not all teethin the mouth, and/or it can include a single tooth.

A positive model and/or negative impression of the patient's teeth or atooth may be scanned using an X-ray, laser scanner, destructive scanner,structured light, and/or other range acquisition system to produce theIOD. The data produced by the range acquisition system may be convertedto other formats to be compatible with the software which is used formanipulating images within the data, as described herein.

Referring now to FIG. 1A, there is illustrated an initial virtual dentalmodel 100 according to one or more embodiments of the presentdisclosure. As described herein, the initial virtual dental model 100can be obtained from a first scan of a patient dentition prior totreatment or at an intermediate state of treatment (e.g., beforetreatment has been completed) or the final scan of a certain treatmentphase. One or more embodiments of the present disclosure includereceiving a virtual IOD and a desired position of a tooth contained inthe virtual IOD. The initial virtual dental model (e.g., virtual IOD)can also include a model of an individual tooth (e.g., tooth 102-1) thatis part of a full dental model, such as full virtual dental model 100.

FIG. 1B illustrates a target virtual dental model 104. The targetvirtual dental model 104 can be created by modifying the initial virtualdental model 100 according to one or more treatment goals of a treatmentplan. The one or more treatment goals can be case-specific (e.g.,specific to the particular patient on which the initial virtual dentalmodel 100 was based). The target virtual dental model 104 can alsoinclude a target model of an individual tooth (e.g., tooth 102-2) thatis part of a full dental model similar to full target dental model 104.In some embodiments, the virtual IOD 100 and the target virtual dentalmodel 104 can be displayed via a user interface in three dimensions.

Treatment plans are designed by beginning with a current teethconfiguration (e.g., the virtual IOD 100), determining the targetvirtual dental model 104, generating a path for the teeth from thevirtual IOD to the target configuration, and segmenting that path intomultiple segments to form the appliances. Embodiments of the presentdisclosure can virtually identify and test the force applied to teeth bya designed appliance or physical feature can be used to determine whatthe actual resulting configuration of teeth would be based upon thealigner proposed in the treatment plan versus the intendedconfiguration.

In some embodiments, these forces can include forces from any dentalappliances on the tooth, forces from neighboring teeth, gingival forcesapplied and modified based on effects from other teeth on the set andtheir forces and/or movements, forces from bone structures and/or otherforces that may affect the tooth. In some embodiments, the appliancewall thickness and feature data (e.g., dimples, reinforcementstructures, shape, orientation with respect to one or more teeth, etc)can be used to determine the actual resulting configuration of teethversus the intended configuration. The force information can be measuredbased on an actual appliance and/or estimated based upon thicknesssampling of measurements taken from other appliances that have beenpreviously measured.

Virtually identifying and/or testing forces can be utilized in theoptimization for products for use in the mouth of a patient, such asaligners, anchors, attachments, and other dental appliances, andpotentially to appliance surfaces (e.g., dimples, ridges, thickness,shape, orientation, etc.), appliance material properties, and theirinteraction with the teeth. Virtually identifying and testing one ormore applied forces allows a user to identify the forces present on aset of teeth from a dental appliance and to optimize the dentalappliance shape and/or position such that desired forces are acting onthe teeth to move teeth along a particular segment of the treatmentplan.

Virtually testing an applied force to a tooth can also be beneficial indetermining how much force to apply to the tooth and from what one ormore directions. This information can be used to determine the shapeand/or positioning of the dental appliance to get closest to thenecessary force and/or direction desired for moving the tooth.

FIG. 2 illustrates an example three-dimensional model of teeth (e.g.,the IOD 200), an appliance 204, and an example of a user interface 208for identifying force placed on the teeth 200 according to one or moreembodiments of the present disclosure. The model of teeth can be the IOD200 or can be a position of the teeth in a particular tooth path segmentof the treatment plan (e.g., position subsequent to the startingposition of the treatment plan). For example, each tooth path segment ofthe treatment plan can have corresponding dental appliances or applianceconfigured to move the teeth from a subsequent position of the toothpath segment to another position closer to a final position of thetreatment plan.

In one or more embodiments, a user can virtually place the dentalappliance 204 with, for example, a cavity geometry of the first stage ofthe treatment plan over the IOD 200 and identify actual forces appliedto the teeth contained in the IOD 200 from the dental appliance 204based on the dental appliance material properties, characteristics,and/or shape of the teeth.

For example, the elastic deformation of the dental appliance based onthe appliance material properties, characteristics, and shape of teethcan determine an amount of stress on the appliance, a force and/ortorque applied to each tooth, and/or individual contacts of the aligneron teeth and their relative strength. Knowing the forces acting on thedental appliance and on the teeth allows a user to more accuratelycreate the dental appliance characteristics to most efficiently move theteeth from an initial position to a final position of the treatment plancorresponding to a dental appliance.

FIG. 3 illustrates examples of three-dimensional dental appliances andan example of a user interface 308 for identifying force on the dentalappliance and applied to the virtual set of teeth (e.g., the IOD 200 inFIG. 2 ) according to one or more embodiments of the present disclosure.In one or more embodiments, a user can virtually identify force placedon the dental appliance and to the teeth when the dental appliance isplaced over the IOD.

As seen in FIG. 3 , there are three three-dimensional dental appliancesdisplayed on the user interface 308. The first dental appliance 310illustrates an amount of internal stress acting on the dental appliancewhen placed on the IOD. The amount of stress is indicated as a lightnumber of dots to a heavier number of dots scale. For example, areas ofthe dental appliance 310 that have a low amount of stress are displayedas a light number of dots, whereas areas of the dental appliance 310having higher amounts of stress are displayed as heavier number of dots.

The second dental appliance 312 in the user interface 308 illustrates aforce and torque applied to each tooth. Vectors 314 can represent theforce applied to a tooth by the dental appliance. Additionally, thevectors 316 can represent the torque applied to the teeth from thedental appliances. The vectors can represent the force, the torque,and/or the magnitude of each.

The third dental appliance 318 in the user interface 308 illustratesindividual contacts of the dental appliance on the teeth and therelative strength of the contact. For example, arrows 320 can illustratethe direction and the magnitude of the local force where the dentalappliance contacts the teeth.

By identifying the actual forces acting on the dental appliance and onthe teeth, the dental appliance and features of the dental appliance maybe editable by a user such that the actual forces are sufficientlysimilar to desired forces as discussed further herein.

For one or more embodiments, once the actual forces of the dentalappliance on the tooth are identified, one or more desired forces to beapplied by the dental appliance to move the teeth to the first stageteeth positions are determined. FIG. 4 illustrates an examplethree-dimensional tooth model and an example of a user interface 408 fordetermining desired force and torque placed on a tooth 422 according toone or more embodiments of the present disclosure.

In one or more embodiments, a user can virtually test the shape and/orplacement of a dental appliance or other appliance structure (e.g.,physical feature 421-1) and make adjustments to the shape or placementand retry the movement until the best or most satisfactory result isachieved.

The model of tooth 422 includes arrows 426-1 and 426-2 representing adesired force and torque components for movement of tooth 422. Forexample, arrows 426-1 and 426-2 can represent an ideal force and torquecomponents for movement.

The model of tooth 422 also includes tooth surface feature 424-1 (e.g.,dental appliance, dimple, etc.) and an arrow 424-2 that can represent adesired feature force direction and/or magnitude, given a set ofphysical and/or appliance characteristics. A feature or features (e.g.,feature 424-1) can apply a force and/or torque to the tooth 422, whichcan be represented by arrow 424-2.

A possible location 428 where a feature 424-1 can be placed on tooth 422can also be available on the tooth model and user interface 408. Thetooth, as well as features of the dental appliance may be editable by auser as further discussed herein.

For one or more embodiments, once the desired forces for moving one ormore teeth are identified, an aligner cavity geometry and/or position toreach the desired forces can be optimized to move the teeth to thedesired teeth positions based on the dental appliance materialproperties, characteristics, and shape of teeth. Designing optimizedaligner cavity geometry and/or position can include virtually testingand adjusting the dental appliance iteratively to reach the desiredforces for moving the teeth to the first stage teeth location.

FIG. 5 illustrates an example three-dimensional tooth model and anexample of a user interface 508 for testing force placed on a tooth 522according to one or more embodiments of the present disclosure. In someembodiments, a user can take data from an actual patient's mouth or atypodont and determine the forces desired during a portion of atreatment plan to move a tooth from one position to another. A typodontcan refer to a virtual dental model including a number of ideal toothshapes (e.g., from a reference library of idealized tooth shapes).

The use of actual case data may be useful, for example, where a dentalappliance may be desired to perform a particular movement with respectto a particular tooth positioning due to a particular malocclusion. Insome embodiments, a user can enter physical parameters of a dentalappliance (e.g., appliance, aligner, dimple, etc.) to be created oraltered into a location and orientation window 530.

For example, a user can enter such parameters as a length 532, a width534, a prominence 536, a depth 538 of inside tooth 522, an activationangle 540, and an activator offset on inactive surfaces 542. In someembodiments, the system can be configured to allow a user to othersettings, such as an iso-surface gradient width 544 and a voxel size546. In various embodiments, a user can choose to identify tooth 522 bya number or some other identifier and enter or choose the identifier ina drop-down box such as box 548. A user can also choose to enterparameters for a center of the dental appliance and an active surface(e.g., parameters 550 and 552).

In some embodiments, a user interface (e.g., user interface 508) isprovided where a virtual model of the tooth is presented in threedimensions. Once the forces and moments of the forces on the tooth aredetermined, they can be presented on the user interface (e.g., they canbe presented as vector arrows showing direction and/or magnitude ofdesired force or stress) among other information about the force thatmay be helpful to the user.

Vector arrows 526-1 and 526-2 can represent desired (e.g., ideal) forceand/or torque for movement of tooth 522, and vector arrow 554 canrepresent a force and torque applied to tooth 522 by a feature 524-1.Vector arrow 524-2 can represent a desired (e.g., optimal) feature forcedirection and magnitude, given a set of features (e.g., dentalappliance, dimple, etc).

Treatment plan case data can be analyzed to determine the movement of aparticular tooth from a first position e.g., initial position orintermediate position that is prior to the subsequent position) to asubsequent (e.g., desired) position. This information can then beutilized in an analysis of forces with respect to proposed dentalappliances or other aligner related movement analysis.

Tools for the creation and/or alteration of the dental appliances orother items related to the movement of the tooth can be utilized tovirtually test force placed on a tooth in some embodiments. These itemscan include one or more libraries of tooth shapes and treatment plandata (e.g., typodonts, actual patient tooth data, and/or treatment plandata), dental appliance shapes, data regarding mounting materials thatcould be used, and/or data regarding other characteristics of analigner, tooth, and/or mouth structure.

The items can also include editing tools to change the shape of thedental appliances or other items related to the movement of the tooth.For example, suitable tools could include those typically provided withrespect to drafting and/or computer aided design software applications.

As discussed, in some embodiments, the desired forces and the actualforces can be illustrated on the virtual model so that the user can seethe differences between the actual and desired forces (e.g., forceand/or magnitude vectors for both the desired and actual forces). Thiscan be helpful, for example, by allowing the user to see the differencesand adjust the shape or position of the dental appliance or other itemrelated to the movement of the tooth. The actual force can then berecalculated and/or illustrated to show the revised force of the revisedshape and/or position.

Also as discussed above, in some embodiments, multiple calculatedpositions and/or shapes can be illustrated (e.g., the forces generatedfrom a first position and a second position can be illustrated togetherand, in some instances, with the desired forces). This can bebeneficial, for example, to identify how the change from a first to asecond position affected the forces. It can also be beneficial toidentify if the change from a first to a second position is adjustingthe forces created closer to those of the desired forces.

It should be noted that one force that may be quantified for movement ofthe tooth is for total movement of the tooth from a first position to asecond position. However, forces from the gingiva and bone interactionsfor some force calculations can also be incorporated and, therefore, insome embodiments, forces for different stages of movement can bedetermined, such as initial force needed for bone breakdown versus forceneeded for movement once the bone restructuring has occurred. Forexample, in some embodiments, the movement from a first position to asecond position may be determined by calculating the force sufficient toenable the tooth to begin to move (e.g., the first and second positionscould be relatively close or adjacent and therefore the force to createthat movement would be the force needed to begin moving the tooth).

Modeling techniques involving gingival or bone structures can, forexample, be accomplished by modeling the root structure and/or thestructure of the jaw bone and/or gingiva. This can, for instance, beaccomplished using patient data and/or typodont data.

In some embodiments, a center of mass can be calculated for the tooth,and the forces (e.g., desired forces) can be associated with the centerof mass. In some embodiments, a center of rotation can be calculated,and the forces can be associated with the center of rotation.

In some embodiments, a possible placement area 528 in which anattachment can be positioned on a tooth can be identified. Thisinformation can be obtained through experiential data programmed intothe software and/or entered by the user or multiple users. Additionally,this can be calculated based upon the forces that are to be generated.

For example, in some embodiments, the forces generated can be determinedfor an attachment that has been selected by the user for placement onthe tooth and a possible placement area 528 can be identified for theplacement of the attachment on the tooth. The possible placement area528 can, for example, be based upon where the placement of theattachment would result in a certain result that would be within athreshold proximity to the desired result. In some embodiments, as theshape and/or orientation of the dental appliance is changed, thepossible placement area can be recalculated.

The possible placement area 528 could, for instance, be based on areaswhere attachment could actually be achieved (e.g., portions of the toothwhere an attachment would be sufficiently adhered to the tooth so thatit does not come detached or obstructed by a structure such as a toothsurface not being shaped for attachment thereto or too far below thegingiva). This calculation could be determined through experiential dataor based upon one or more characteristics of the tooth, and/or materialsto be used (e.g., adhesion characteristics of the tooth surface,adhesion characteristics of the adhesion material, adhesioncharacteristics of the dental appliance material, shape of the adhesionsurface of the attachment, and/or shape of the surface of the tooth,etc).

For example, the possible placement area 528 may not include the edgeareas, overly curved surfaces, and/or contoured surfaces of the toothbecause adhesion to those surfaces may be difficult, in some situations.It may not be reasonable to use some areas of the tooth, as certainareas would not properly associate or connect with a surface of anappliance, and as such, in some embodiments, association informationand/or surface information can be used in determining possible placementareas.

For example, improper association can include, for instance, anappliance position that is calculated to be undesirably close to or incontact with a neighboring tooth, an appliance position that negativelyimpacts a neighboring tooth and/or area surrounding the possibleplacement area, a position that would not provide proper fit between theattachment and another appliance such as an aligner, and/or negativelyimpacting the area around an aligner and/or the appliance, among others.Improper connection with a surface of an appliance can include, forinstance, can include not having a tooth surface that would provide asecure bonding surface for attachment of an appliance thereon, amongothers.

In some embodiments, the possible placement area 528 may by “dynamic” inthat it can change as certain criteria (e.g., the shape and/or type ofappliance, bonding material, material of the appliance, etc.) changes.For example, an attachment of a particular shape may have morepreferable results when placed on a first area of a tooth than a secondattachment having a second shape, perhaps, with a different surfaceshape on the surface to be bonded to the surface of the tooth andtherefore, the possible placement area can be changed so that the userinterface can indicate the changes to a user.

As discussed herein, in one or more embodiments, a user can virtuallyplace a dental appliance such as an appliance over the IOD to identifyforces acting on the appliance. For example, identifying forces actingon the appliance can determine if the appliance will relax and wheresuch relaxation will occur. This can be beneficial, for example, toidentify points in which the appliance should be reinforced to reduce oreliminate the relaxation.

FIG. 6 illustrates a system for virtually identifying force placed on atooth according to one or more embodiments of the present disclosure. Inthe system illustrated in FIG. 6 , the system includes a computingdevice 656 having a number of components coupled thereto. The computingdevice 656 includes a processor 658 and memory 660. The memory 660 caninclude various types of information including data 662 and executableinstructions 664 discussed herein.

Memory and/or the processor may be located on the computing device 656or off the device in some embodiments. As such, as illustrated in theembodiment of FIG. 6 , a system can include a network interface 666.Such an interface can allow for processing on another networkedcomputing device or such devices can be used to obtain information aboutthe patient or executable instructions for use with various embodimentsprovided herein.

As illustrated in the embodiment of FIG. 6 , a system can include one ormore input and/or output interfaces 668. Such interfaces can be used toconnect the computing device with one or more input or output devices.

For example, in the embodiment illustrated in FIG. 6 , the system caninclude connectivity to a scanning device 670, a camera dock 672, aninput device 674 (e.g., a keyboard, mouse, etc.), a display device 676(e.g., a monitor), a printer 678, and one or more other input devices.The input/output interface 668 can receive data, storable in the datastorage device (e.g., memory 660), representing a digital dental modelof a patient's dentition.

In some embodiments, the scanning device 670 can be configured to scanone or more physical molds of a patient's dentition. In one or moreembodiments, the scanning device 670 can be configured to scan thepatient's dentition directly. The scanning device 670 can be configuredto input data to the application modules 680.

The camera dock 672 can receive an input from an imaging device (e.g., atwo-dimensional imaging device) such as a digital camera or a printedphotograph scanner. The input from the imaging device can be stored inthe data storage device (e.g., memory 660).

The processor 658 can be configured to provide a visual indication of avirtual dental model on the display 676 (e.g., on a GUI running on theprocessor 658 and visible on the display 676). The GUI can be configuredto allow a treatment professional or other user to input treatmentgoals, to create a target virtual dental model 602, and/or enter desiredor actual dental appliance parameters. Input received via the GUI can besent to the processor 658 as data and/or can be stored in memory 660.

Such connectivity can allow for the input and/or output of data and/orinstructions among other types of information. Although some embodimentsmay be distributed among various computing devices within one or morenetworks, such systems as illustrated in FIG. 6 can be beneficial inallowing for the capture, calculation, and/or analysis of informationdiscussed herein.

The processor 658, in association with the data storage device (e.g.,memory 660), can be associated with data and/or application modules 680.The processor 658, in association with the memory 660, can store and/orutilize data and/or execute instructions to provide a number ofapplication modules for virtually testing force placed on a tooth.

Such data can include the initial virtual dental model 600 and thetarget virtual dental model 602. Such application modules can include acreation module 682, a verification module 684, an identification module686, and/or a display module 688.

The computation module 684 can be configured to compute a desiredposition, a desired orientation, and a desired relative magnitude ofpoint contact force of a dental appliance to achieve the target virtualdental model 602. Additionally, the computation module can determine adesired force that is present on the dental appliance based on thedental appliance material properties, characteristics, and shape ofteeth.

The creation module 682 can be configured to virtually create a dentalappliance based on a treatment plan. For example, the creation module682 can create a plurality of dental appliances, such as appliances,that are configured to move teeth from the initial virtual dental model600 to the target virtual dental model 602, where each appliance isconfigured to move the teeth a portion of the path from the initialdental model 600 to the target virtual dental model 602. In someembodiments, a single dental appliance can be used to move the teeth tothe target virtual dental model 602.

The identification module 686 can be configured to identify actualforces present on the created dental appliance and on the teeth andverify the dental appliance is applying the desired force parameters tothe teeth contained in the initial virtual dental model. For example,the identification module 686 can test the virtually created dentalappliance and verify it has the desired position, orientation, relativemagnitude of point contact force, a desired amount of stress, anddesired individual contacts of the dental appliance.

The display module 688 can be configured to display the virtuallycreated dental appliance and the point contact force. The display module688 can be configured to display the information on display device 676.

FIG. 7 is a flow chart illustrating a method for identifying forceplaced on teeth according to one or more embodiments of the presentdisclosure. At 790, initial virtual orthodontic data (IOD) of teeth isreceived.

The IOD may be received in a variety of ways and may contain a varietyof information. For example, the IOD can include a gum structure and amouth bone structure, along with an initial teeth or tooth model.

The patient's teeth may be imaged to obtain digital data using directand/or indirect structured light, X-rays, three-dimensional X-rays,lasers, destructive scanning, computer-aided tomographic images and/ordata, magnetic resonance images, intra-oral scanning technology,photographic reconstruction, and/or other imaging techniques. The IODcan include any portion of the mouth, from an entire mouth tootharrangement to a single tooth.

A positive model and/or negative impression of the patient's teeth or atooth may be scanned using an X-ray, laser scanner, destructive scanner,structured light, and/or other scanning system to produce data for theIOD. In some embodiments, the data produced by the scanning system maybe converted to other formats to be compatible with the software whichis used for manipulating images within the data.

A desired tooth position of a treatment plan for the teeth contained inthe virtual IOD is received at 792. The desired position may be thechoice of a treatment professional and/or the patient. The desiredposition can also be a position that has been used for previous patientswith similar teeth positioning.

At 794, a desired force and/or torque to be applied to the teeth inorder to reach the desired tooth positions is computed. The force and/ortorque can be applied using a dental appliance (e.g., appliance, dimple,etc.). Using this desired force and/or torque, a dental appliance can bevirtually created using a number of aforementioned creation toolsinclude editing tools to change the shape of the dental appliances orother items related to the movement of the tooth. The dental appliancecan be optimally adjusted at 796 until the desired force and torque formoving the tooth from an initial position to the desired position isreached.

In some embodiments, an actual force generated by a dental appliancechosen by a patient, treatment professional, and/or other user can bedetermined. Based on this actual force, an area for the placement of thedental appliance on the tooth can be chosen.

An area for the placement of the dental appliance on the tooth can alsobe determined without the actual force determination. The desired forceand torque to be applied to the tooth can be compared to the determinedactual force, and the results can be presented to a user via a userinterface.

This can be helpful, for example, by allowing the user to seedifferences and adjust the shape or position of the dental appliance orother item related to the movement of the tooth. The actual force can berecalculated and/or illustrated to show a revised force of the revisedshape and/or position.

For example, the desired position, desired orientation, and/or desiredrelative magnitude of point contact force can be recomputed with a newconstraint if the dental appliance does reach the desired outcome,treatment goal, or model. The dental appliance can also be recreatedwith a different shape if desired outcomes are not met.

At 798, aligner structural elements are designed including optimizedcomponents given material properties to deliver a desired force. Oncethe forces and/or moments of the forces on the tooth are determined,they can be presented on the user interface (e.g., they can be presentedas vector arrows showing direction and/or magnitude of desired force)among other information about the force that may be helpful to the user.

Virtually identifying force placed on a tooth and the dental appliancecan be beneficial for many reasons, including the utilization of realworld force information, tooth data, and/or other structural data tocalculate the position for placement and/or potential shape of a dentalappliance or other appliance feature without actually having to test allof these iterations in an actual patient or group of patients. Theresults can include more accurate movement of teeth, thereby reducingthe time of treatment and increasing patient satisfaction, among others.

These embodiments are described in sufficient detail to enable those ofordinary skill in the art to practice one or more embodiments of thisdisclosure. It is to be understood that other embodiments may beutilized and that process, electrical, and/or structural changes may bemade without departing from the scope of the present disclosure.

As will be appreciated, elements shown in the various embodiments hereincan be added, exchanged, combined, and/or eliminated so as to provide anumber of additional embodiments of the present disclosure. Theproportion and the relative scale of the elements provided in thefigures are intended to illustrate the embodiments of the presentdisclosure, and should not be taken in a limiting sense.

As used herein, “a” or “a number of” something can refer to one or moresuch things. For example, “a number of computing devices” can refer toone or more computing devices.

Although specific embodiments have been illustrated and describedherein, those of ordinary skill in the art will appreciate that anyarrangement calculated to achieve the same techniques can be substitutedfor the specific embodiments shown. This disclosure is intended to coverany and all adaptations or variations of various embodiments of thedisclosure.

It is to be understood that the above description has been made in anillustrative fashion, and not a restrictive one. Combination of theabove embodiments, and other embodiments not specifically describedherein will be apparent to those of skill in the art upon reviewing theabove description.

The scope of the various embodiments of the disclosure includes anyother applications in which the above structures and methods are used.Therefore, the scope of various embodiments of the disclosure should bedetermined with reference to the appended claims, along with the fullrange of equivalents to which such claims are entitled.

In the foregoing Detailed Description, various features are groupedtogether in example embodiments illustrated in the figures for thepurpose of streamlining the disclosure. This method of disclosure is notto be interpreted as reflecting an intention that the embodiments of thedisclosure require more features than are expressly recited in eachclaim.

Rather, as the following claims reflect, inventive subject matter liesin less than all features of a single disclosed embodiment. Thus, thefollowing claims are hereby incorporated into the Detailed Description,with each claim standing on its own as a separate embodiment.

What is claimed is:
 1. A non-transitory computing device readable mediumhaving instructions that can be executed by a processor to: generate atreatment plan including a segmented path for virtual teeth from aninitial virtual dental model to a target virtual dental model, eachsegment having a corresponding virtual dental appliance to move thevirtual teeth to a subsequent segment, wherein the initial virtualdental model that is based on initial orthodontic data (IOD) of physicalteeth; virtually identify and test force applied to the virtual teeth bythe corresponding virtual dental appliance of a particular segment ofthe treatment plan and a virtual tooth surface feature placed on one ofthe virtual teeth; determine a resulting configuration of the virtualteeth based on the virtual identifying and testing; provide an editingtool operable by a user to adjust a shape or placement of the virtualtooth surface feature to improve the resulting configuration; virtuallyreidentify and retest force applied to the virtual teeth by thecorresponding virtual dental appliance and the virtual tooth surfacefeature after the adjustment; determine a resulting configuration of thevirtual teeth based on the virtual reidentifying and retesting; andoutput, via an output interface, an identification of a placement of anactual feature, corresponding to the placement of the virtual toothsurface feature, on an actual tooth, corresponding to the one of thevirtual teeth.
 2. The medium of claim 1, the instructions furtherexecutable to receive an edit to adjust a shape of the correspondingvirtual dental appliance.
 3. The medium of claim 2, the instructionsfurther executable to: virtually identify and test force applied to thevirtual teeth by the adjusted dental appliance and virtual tooth surfacefeature after the adjustment; and determine a new resultingconfiguration of the virtual teeth based on the virtual identifying andtesting for the adjusted dental appliance and adjusted feature.
 4. Themedium of claim 3, the instructions further executable to illustrate theforce applied to the teeth by the corresponding virtual dental applianceon the initial virtual dental model and simultaneously illustrate theforce applied to the teeth by the dental appliance and virtual toothsurface feature after the adjustment on the initial virtual dentalmodel.
 5. The medium of claim 2 wherein the instructions to receive theedit to the virtual tooth surface feature comprise instructions toreceive an edit to one or more of a group of virtual tooth surfacefeatures including a dimple, a reinforcement structure, a shape, and anorientation with respect to the teeth.
 6. A system for virtuallyidentifying and testing force applied to teeth, comprising: a processor;memory having instructions executable by the processor to: determine atarget virtual dental model for an initial virtual dental model that isbased on initial orthodontic data (IOD) of physical teeth; generate atreatment plan including a segmented path for virtual teeth from theinitial virtual dental model to the target virtual dental model, eachsegment having a corresponding virtual dental appliance to move thevirtual teeth to a subsequent segment; virtually identify and test forceapplied to the virtual teeth by each corresponding virtual dentalappliance of the treatment plan and a virtual tooth surface featureplaced on one of the virtual teeth; determine a resulting configurationof the virtual teeth after each segment based on the virtual identifyingand testing versus the treatment plan; receive an adjustment to a shapeor placement of the virtual tooth surface feature to improve theresulting configuration; virtually reidentify and retest force appliedto the virtual teeth by each corresponding virtual dental appliance andthe virtual tooth surface feature after the adjustment; determine aresulting configuration of the virtual teeth based on the virtualreidentifying and retesting; and output, via an output interface, anidentification of a placement of an actual feature, corresponding to theplacement of the virtual tooth surface feature, on an actual tooth,corresponding to the one of the virtual teeth.
 7. The system of claim 6,the instructions further executable to virtually identify and test forceapplied to the teeth by each corresponding virtual dental appliance andby virtual gingiva and bone interactions.
 8. The system of claim 7, theinstructions further executable to virtually identify and test forceapplied to the teeth by a particular virtual dental appliance for bonebreakdown.
 9. The system of claim 8, wherein the force applied to theteeth by the particular virtual dental appliance comprises a forcesufficient to enable the virtual teeth to begin moving at a start of thetreatment plan.
 10. The system of claim 7, the instructions furtherexecutable to virtually identify and test force applied to the virtualteeth by a particular virtual dental appliance for movement after bonerestructuring has occurred.